| 401 | John E. McCool | Youngsville, PA 16371 | Oil Operator | Dec 2020 |
| 402 | John H Hendrix Corp | Midland, TX 797023040 | Oil & Gas Operator | Sep 2018 |
| 403 | John L Cox | Midland, TX 79701 | Oil & Gas Operator | Dec 2003 |
| 404 | Joint Resources Company | Fort Worth, TX 76107 | Oil & Gas Operator | Mar 2025 |
| 405 | Journey Operating, L.L.C. | Sugar Land, TX 77496 | Oil & Gas Operator | Aug 2006 |
| 406 | JPH Oil Producers Dba Jimmy P Hodge | Lovington, NM 88260 | Oil & Gas Operator | Jan 2025 |
| 407 | Jr Cone Operating, LLC | Lubbock, TX 79408 | Oil & Gas Operator | Jan 2025 |
| 408 | Judah Oil LLC | Artesia, NM 88211 | Oil & Gas Operator | Jan 2025 |
| 409 | Julian Ard | Fort Worth, TX 76102 | Oil & Gas Operator | Jul 2002 |
| 410 | Jumbo American Petroleum Corporation | Midland, TX 79701 | Oil & Gas Operator | Apr 2010 |
| 411 | Justice Oil Co | Hobbs, NM 88241 | Oil & Gas Operator | Dec 1996 |
| 412 | K P Kauffman Company Inc | Denver, CO 80203 | Oil & Gas Operator | Jan 2025 |
| 413 | K&M Resources LLC | Artesia, NM 88211 | Oil & Gas Operator | Jan 2025 |
| 414 | Kaiser-Francis Oil Company | Tulsa, OK 74121 | Oil & Gas Operator | Mar 2025 |
| 415 | KC Resources Inc | Snowmass VLG., CO 81615 | Oil & Gas Operator | Dec 2024 |
| 416 | KCS Resources, LLC | Houston, TX 77027 | Oil & Gas Operator | Feb 2017 |
| 417 | Kelly H. Baxter | Austin, TX 78767 | Oil & Gas Operator | Nov 2006 |
| 418 | Kelt Oil & Gas, Inc. | Torrance, CA 90503 | Oil & Gas Operator | Dec 2003 |
| 419 | Kem Ventures, LP | Katy, TX 77450 | Oil & Gas Operator | Jan 2025 |
| 420 | Kenson Operating Company Inc | Houston, TX 77002 | Oil & Gas Operator | Sep 2002 |
| 421 | Kent Walker | Midland, TX 79708 | Oil & Gas Operator | Sep 1999 |
| 422 | Kern Co. | Houston, TX 77095 | Oil & Gas Operator | Jan 2021 |
| 423 | Kerns Petroleum, Inc. | San Antonio, TX 78257 | Oil & Gas Operator | Sep 2013 |
| 424 | Kerr-McGee Oil & Gas Onshore LP | Houston, TX 77046 | Oil & Gas Operator | Mar 2025 |
| 425 | Kersey & Company | Ellijay, GA 30540 | Oil & Gas Operator | Jan 2023 |
| 426 | Kevin O Butler & Assoc Inc | Midland, TX 79702 | Oil & Gas Operator | Mar 2024 |
| 427 | Kinder Morgan Production Co LP | Midland, TX 79701 | Oil & Gas Operator | Jul 2007 |
| 428 | Kindred Petroleum Company | Midland, TX 79702 | Oil & Gas Operator | Mar 2025 |
| 429 | Kinlaw Oil Corporation | Dallas, TX 75380 | Oil & Gas Operator | Mar 2025 |
| 430 | Kinney Incorporated | Andrews, TX 79714 | Oil & Gas Operator | Mar 2025 |
| 431 | Knox Industries, Inc. | Arlington, TX 76012 | Oil & Gas Operator | Mar 2025 |
| 432 | Kratos Operating, LLC | Hobbs, NM 88241 | Oil & Gas Operator | Nov 2024 |
| 433 | Kukui Inc | Houston, TX 77002 | Oil & Gas Operator | Dec 2002 |
| 434 | Kukui Operating Company | Ignacio, CO 81137 | Oil & Gas Operator | May 2013 |
| 435 | L E Jones Operating Inc | Duncan, OK 73534 | Oil & Gas Operator | Jan 2025 |
| 436 | L R French Jr | Midland, TX 79701 | Oil & Gas Operator | Aug 2014 |
| 437 | L. B. Simmons Energy, Inc. | Midland, TX BAD ADDR | Oil & Gas Operator | Oct 1996 |
| 438 | Landmark Energy Partners, LLC | Edmond, OK 73013 | Oil Operator | Dec 2024 |
| 439 | Lanexco, Inc. | Sealy, TX 77474 | Oil & Gas Operator | Mar 2025 |
| 440 | Lariat Petroleum Inc | Tulsa, OK 74119 | Oil & Gas Operator | Sep 2024 |
| 441 | Lario Oil & Gas Company | Odessa, TX 79762 | Oil & Gas Operator | Mar 2025 |
| 442 | Larry Marker Dba Marker Oil | Roswell, NM 88202 | Oil & Gas Operator | Jul 2017 |
| 443 | Las Animas Production Company | Midland, TX 79705 | Oil & Gas Operator | Mar 1995 |
| 444 | Latigo Petroleum, Inc. | Tulsa, OK 74119 | Oil & Gas Operator | Dec 2024 |
| 445 | Lawson Operating LLC | Midland, TX 79710 | Oil & Gas Operator | Oct 2015 |
| 446 | Layton Enterprises, Inc. | Lubbock, TX 79423 | Oil & Gas Operator | Apr 2007 |
| 447 | Lbo New Mexico Inc | Midland, TX BAD ADDR | Oil & Gas Operator | Dec 1996 |
| 448 | Leaco Operating, LLC | Houston, TX 77056 | Oil Operator | Jan 2025 |
| 449 | Legacy Reserves Operating LP | Denver, CO 80201 | Oil & Gas Operator | Mar 2025 |
| 450 | Leigh Operating Co | Dallas, TX 75205 | Oil & Gas Operator | Mar 2008 |
| 451 | Leopoldo P Bustamante | Midland, TX 79710 | Oil & Gas Operator | Apr 2012 |
| 452 | Lime Rock Resources A, L.P. | Houston, TX 77002 | Oil & Gas Operator | Dec 2024 |
| 453 | Lime Rock Resources II-A, L.P. | Houston, TX 77002 | Oil & Gas Operator | Dec 2024 |
| 454 | Lindenmuth & Associates Inc | Austin, TX 78703 | Oil & Gas Operator | Aug 2024 |
| 455 | Linn Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Jan 2019 |
| 456 | Lion Production, Inc. | Midland, TX 79702 | Oil & Gas Operator | Mar 2006 |
| 457 | Llano Production Company | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2025 |
| 458 | LLJ Ventures, LLC Dba Marker Oil & Gas | Roswell, NM 88202 | Oil & Gas Operator | Apr 2022 |
| 459 | Lobo Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Oct 1995 |
| 460 | Lodestone Operating, Inc. | Portland, TX 78374 | Oil & Gas Operator | Mar 2025 |
| 461 | Lone Star Oil & Gas, Inc | Greenville, KY 42345 | Oil & Gas Operator | Dec 2022 |
| 462 | Long Trust The | Kilgore, TX 75663 | Oil & Gas Operator | Aug 2008 |
| 463 | Lothian Oil Texas I, Inc. | Dallas, TX 75204 | Oil & Gas Operator | Mar 2008 |
| 464 | Louis Dreyfus Natural Gas Inc | Houston, TX 770103088 | Oil & Gas Operator | Sep 1997 |
| 465 | Lynx Operating Co., Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2025 |
| 466 | Lynx Petroleum Consultants Inc. | Hobbs, NM 88241 | Oil & Gas Operator | Feb 2024 |
| 467 | M & L Enterprises A Partnership | Hobbs, NM 88240 | Oil & Gas Operator | Feb 2001 |
| 468 | M & W Of Lovington Inc | Lovington, NM 88260 | Oil & Gas Operator | Jan 2011 |
| 469 | M Brad Bennett Inc | Midland, TX 797101510 | Oil & Gas Operator | Jul 2006 |
| 470 | M C Gandy & Dale Gandy | Hobbs, NM BADADDR | Oil Operator | Sep 2008 |
| 471 | M E W Enterprise | Roswell, NM 88203 | Oil & Gas Operator | Aug 2024 |
| 472 | M G Oil Inc | Russell, KS 67665 | Oil Operator | Nov 2024 |
| 473 | M R Drilling Company | Monahans, TX 79756 | Oil & Gas Operator | Feb 1998 |
| 474 | M&M Energy, LLC | El Paso, TX 79902 | Oil Operator | Dec 2020 |
| 475 | M-T Petroleum, Inc. | Andrews, TX 79714 | Oil & Gas Operator | Mar 2008 |
| 476 | M7 Resources LLC | Santa Fe, NM 87505 | Oil Operator | Dec 2024 |
| 477 | Mack Energy Corporation | Artesia, NM 88211 | Oil & Gas Operator | Jan 2025 |
| 478 | Magnum Hunter Production, Inc. | Irving, TX 75014 | Oil & Gas Operator | Dec 2019 |
| 479 | Mammoth Exploration LLC | Midland, TX 79701 | Oil & Gas Operator | Jul 2023 |
| 480 | Manhattan Petroleum, Inc. | Midland, TX 79702 | Oil & Gas Operator | Mar 2025 |
| 481 | Manzano LLC | Roswell, NM 88202 | Oil & Gas Operator | Mar 2025 |
| 482 | Manzano Oil Corporation | Roswell, NM 88202 | Oil & Gas Operator | Feb 2005 |
| 483 | Mar Oil & Gas Corp. | Santa Fe, NM 87502 | Oil & Gas Operator | Jan 2025 |
| 484 | Maralo, LLC | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 485 | Marathon Oil Company | Houston, TX 77024 | Oil & Gas Operator | Jan 2025 |
| 486 | Marathon Oil Permian LLC | Houston, TX 77024 | Oil & Gas Operator | Jan 2025 |
| 487 | Marbob Energy Corp | Artesia, NM 882110227 | Oil & Gas Operator | Oct 2010 |
| 488 | Marcum Drilling Co. | Midland, TX 79701 | Oil & Gas Operator | Aug 2002 |
| 489 | Marjo Operating Co., Inc. | Tulsa, OK 741010729 | Oil & Gas Operator | Dec 2024 |
| 490 | Mark L Shidler Inc | Houston, TX 77055 | Oil & Gas Operator | Jan 2025 |
| 491 | Marks And Garner Production LTD Co | Hobbs, NM 88241 | Oil & Gas Operator | Sep 2010 |
| 492 | Marlin Operating, LLC | Southlake, TX 76092 | Oil & Gas Operator | Jan 2025 |
| 493 | Marshall & Winston, Inc. | Midland, TX 79710 | Oil & Gas Operator | Mar 2025 |
| 494 | Marshall R Young Oil Co | Fort Worth, TX 76102 | Oil & Gas Operator | Feb 1996 |
| 495 | Mas Operating Co. | Midland, TX 79710 | Oil & Gas Operator | Mar 2025 |
| 496 | Matador Operating Company | Dallas, TX 75240 | Oil & Gas Operator | Jul 2003 |
| 497 | Matador Production Company | Dallas, TX 75240 | Oil & Gas Operator | Mar 2025 |
| 498 | Matrix New Mexico Operating Company LLC | Sugarland, TX 77479 | Oil & Gas Operator | Aug 2010 |
| 499 | Maverick Operating, LLC | Midland, TX 79701 | Oil & Gas Operator | Mar 2025 |
| 500 | Maverick Permian LLC | Houston, TX 77002 | Oil & Gas Operator | Mar 2025 |